LXR linux/include/target/target_core

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef TARGET_CORE_FABRIC_H
   3#define TARGET_CORE_FABRIC_H
   4
   5#include <linux/configfs.h>
   6#include <linux/types.h>
   7#include <target/target_core_base.h>
   8
   9struct target_core_fabric_ops {
  10        struct module *module;
  11        /*
  12         * XXX: Special case for iscsi/iSCSI...
  13         * If non-null, fabric_alias is used for matching target/$fabric
  14         * ConfigFS paths. If null, fabric_name is used for this (see below).
  15         */
  16        const char *fabric_alias;
  17        /*
  18         * fabric_name is used for matching target/$fabric ConfigFS paths
  19         * without a fabric_alias (see above). It's also used for the ALUA state
  20         * path and is stored on disk with PR state.
  21         */
  22        const char *fabric_name;
  23        size_t node_acl_size;
  24        /*
  25         * Limits number of scatterlist entries per SCF_SCSI_DATA_CDB payload.
  26         * Setting this value tells target-core to enforce this limit, and
  27         * report as INQUIRY EVPD=b0 MAXIMUM TRANSFER LENGTH.
  28         *
  29         * target-core will currently reset se_cmd->data_length to this
  30         * maximum size, and set UNDERFLOW residual count if length exceeds
  31         * this limit.
  32         *
  33         * XXX: Not all initiator hosts honor this block-limit EVPD
  34         * XXX: Currently assumes single PAGE_SIZE per scatterlist entry
  35         */
  36        u32 max_data_sg_nents;
  37        char *(*tpg_get_wwn)(struct se_portal_group *);
  38        u16 (*tpg_get_tag)(struct se_portal_group *);
  39        u32 (*tpg_get_default_depth)(struct se_portal_group *);
  40        int (*tpg_check_demo_mode)(struct se_portal_group *);
  41        int (*tpg_check_demo_mode_cache)(struct se_portal_group *);
  42        int (*tpg_check_demo_mode_write_protect)(struct se_portal_group *);
  43        int (*tpg_check_prod_mode_write_protect)(struct se_portal_group *);
  44        /*
  45         * Optionally used by fabrics to allow demo-mode login, but not
  46         * expose any TPG LUNs, and return 'not connected' in standard
  47         * inquiry response
  48         */
  49        int (*tpg_check_demo_mode_login_only)(struct se_portal_group *);
  50        /*
  51         * Optionally used as a configfs tunable to determine when
  52         * target-core should signal the PROTECT=1 feature bit for
  53         * backends that don't support T10-PI, so that either fabric
  54         * HW offload or target-core emulation performs the associated
  55         * WRITE_STRIP and READ_INSERT operations.
  56         */
  57        int (*tpg_check_prot_fabric_only)(struct se_portal_group *);
  58        u32 (*tpg_get_inst_index)(struct se_portal_group *);
  59        /*
  60         * Optional to release struct se_cmd and fabric dependent allocated
  61         * I/O descriptor after command execution has finished.
  62         *
  63         * Returning 1 will signal a descriptor has been released.
  64         * Returning 0 will signal a descriptor has not been released.
  65         */
  66        int (*check_stop_free)(struct se_cmd *);
  67        void (*release_cmd)(struct se_cmd *);
  68        void (*close_session)(struct se_session *);
  69        u32 (*sess_get_index)(struct se_session *);
  70        /*
  71         * Used only for SCSI fabrics that contain multi-value TransportIDs
  72         * (like iSCSI).  All other SCSI fabrics should set this to NULL.
  73         */
  74        u32 (*sess_get_initiator_sid)(struct se_session *,
  75                                      unsigned char *, u32);
  76        int (*write_pending)(struct se_cmd *);
  77        void (*set_default_node_attributes)(struct se_node_acl *);
  78        int (*get_cmd_state)(struct se_cmd *);
  79        int (*queue_data_in)(struct se_cmd *);
  80        int (*queue_status)(struct se_cmd *);
  81        void (*queue_tm_rsp)(struct se_cmd *);
  82        void (*aborted_task)(struct se_cmd *);
  83        /*
  84         * fabric module calls for target_core_fabric_configfs.c
  85         */
  86        struct se_wwn *(*fabric_make_wwn)(struct target_fabric_configfs *,
  87                                struct config_group *, const char *);
  88        void (*fabric_drop_wwn)(struct se_wwn *);
  89        void (*add_wwn_groups)(struct se_wwn *);
  90        struct se_portal_group *(*fabric_make_tpg)(struct se_wwn *,
  91                                                   const char *);
  92        void (*fabric_drop_tpg)(struct se_portal_group *);
  93        int (*fabric_post_link)(struct se_portal_group *,
  94                                struct se_lun *);
  95        void (*fabric_pre_unlink)(struct se_portal_group *,
  96                                struct se_lun *);
  97        struct se_tpg_np *(*fabric_make_np)(struct se_portal_group *,
  98                                struct config_group *, const char *);
  99        void (*fabric_drop_np)(struct se_tpg_np *);
 100        int (*fabric_init_nodeacl)(struct se_node_acl *, const char *);
 101
 102        struct configfs_attribute **tfc_discovery_attrs;
 103        struct configfs_attribute **tfc_wwn_attrs;
 104        struct configfs_attribute **tfc_tpg_base_attrs;
 105        struct configfs_attribute **tfc_tpg_np_base_attrs;
 106        struct configfs_attribute **tfc_tpg_attrib_attrs;
 107        struct configfs_attribute **tfc_tpg_auth_attrs;
 108        struct configfs_attribute **tfc_tpg_param_attrs;
 109        struct configfs_attribute **tfc_tpg_nacl_base_attrs;
 110        struct configfs_attribute **tfc_tpg_nacl_attrib_attrs;
 111        struct configfs_attribute **tfc_tpg_nacl_auth_attrs;
 112        struct configfs_attribute **tfc_tpg_nacl_param_attrs;
 113
 114        /*
 115         * Set this member variable to true if the SCSI transport protocol
 116         * (e.g. iSCSI) requires that the Data-Out buffer is transferred in
 117         * its entirety before a command is aborted.
 118         */
 119        bool write_pending_must_be_called;
 120};
 121
 122int target_register_template(const struct target_core_fabric_ops *fo);
 123void target_unregister_template(const struct target_core_fabric_ops *fo);
 124
 125int target_depend_item(struct config_item *item);
 126void target_undepend_item(struct config_item *item);
 127
 128struct se_session *target_setup_session(struct se_portal_group *,
 129                unsigned int, unsigned int, enum target_prot_op prot_op,
 130                const char *, void *,
 131                int (*callback)(struct se_portal_group *,
 132                                struct se_session *, void *));
 133void target_remove_session(struct se_session *);
 134
 135int transport_init_session(struct se_session *se_sess);
 136struct se_session *transport_alloc_session(enum target_prot_op);
 137int transport_alloc_session_tags(struct se_session *, unsigned int,
 138                unsigned int);
 139void    __transport_register_session(struct se_portal_group *,
 140                struct se_node_acl *, struct se_session *, void *);
 141void    transport_register_session(struct se_portal_group *,
 142                struct se_node_acl *, struct se_session *, void *);
 143ssize_t target_show_dynamic_sessions(struct se_portal_group *, char *);
 144void    transport_free_session(struct se_session *);
 145void    target_spc2_release(struct se_node_acl *nacl);
 146void    target_put_nacl(struct se_node_acl *);
 147void    transport_deregister_session_configfs(struct se_session *);
 148void    transport_deregister_session(struct se_session *);
 149
 150
 151void    __target_init_cmd(struct se_cmd *,
 152                const struct target_core_fabric_ops *,
 153                struct se_session *, u32, int, int, unsigned char *, u64);
 154int     target_init_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
 155                unsigned char *sense, u64 unpacked_lun, u32 data_length,
 156                int task_attr, int data_dir, int flags);
 157int     target_submit_prep(struct se_cmd *se_cmd, unsigned char *cdb,
 158                struct scatterlist *sgl, u32 sgl_count,
 159                struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
 160                struct scatterlist *sgl_prot, u32 sgl_prot_count, gfp_t gfp);
 161void    target_submit(struct se_cmd *se_cmd);
 162sense_reason_t transport_lookup_cmd_lun(struct se_cmd *);
 163sense_reason_t target_cmd_init_cdb(struct se_cmd *se_cmd, unsigned char *cdb,
 164                                   gfp_t gfp);
 165sense_reason_t target_cmd_parse_cdb(struct se_cmd *);
 166void    target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *,
 167                unsigned char *, u64, u32, int, int, int);
 168void    target_queue_submission(struct se_cmd *se_cmd);
 169
 170int     target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
 171                unsigned char *sense, u64 unpacked_lun,
 172                void *fabric_tmr_ptr, unsigned char tm_type,
 173                gfp_t, u64, int);
 174int     transport_handle_cdb_direct(struct se_cmd *);
 175sense_reason_t  transport_generic_new_cmd(struct se_cmd *);
 176
 177void    target_put_cmd_and_wait(struct se_cmd *cmd);
 178void    target_execute_cmd(struct se_cmd *cmd);
 179
 180int     transport_generic_free_cmd(struct se_cmd *, int);
 181
 182bool    transport_wait_for_tasks(struct se_cmd *);
 183int     transport_send_check_condition_and_sense(struct se_cmd *,
 184                sense_reason_t, int);
 185int     target_send_busy(struct se_cmd *cmd);
 186int     target_get_sess_cmd(struct se_cmd *, bool);
 187int     target_put_sess_cmd(struct se_cmd *);
 188void    target_stop_session(struct se_session *se_sess);
 189void    target_wait_for_sess_cmds(struct se_session *);
 190void    target_show_cmd(const char *pfx, struct se_cmd *cmd);
 191
 192int     core_alua_check_nonop_delay(struct se_cmd *);
 193
 194int     core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
 195void    core_tmr_release_req(struct se_tmr_req *);
 196int     transport_generic_handle_tmr(struct se_cmd *);
 197void    transport_generic_request_failure(struct se_cmd *, sense_reason_t);
 198int     transport_lookup_tmr_lun(struct se_cmd *);
 199void    core_allocate_nexus_loss_ua(struct se_node_acl *acl);
 200
 201struct se_node_acl *core_tpg_get_initiator_node_acl(struct se_portal_group *tpg,
 202                unsigned char *);
 203bool    target_tpg_has_node_acl(struct se_portal_group *tpg,
 204                const char *);
 205struct se_node_acl *core_tpg_check_initiator_node_acl(struct se_portal_group *,
 206                unsigned char *);
 207int     core_tpg_set_initiator_node_queue_depth(struct se_node_acl *, u32);
 208int     core_tpg_set_initiator_node_tag(struct se_portal_group *,
 209                struct se_node_acl *, const char *);
 210int     core_tpg_register(struct se_wwn *, struct se_portal_group *, int);
 211int     core_tpg_deregister(struct se_portal_group *);
 212
 213int     target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents,
 214                u32 length, bool zero_page, bool chainable);
 215void    target_free_sgl(struct scatterlist *sgl, int nents);
 216
 217/*
 218 * The LIO target core uses DMA_TO_DEVICE to mean that data is going
 219 * to the target (eg handling a WRITE) and DMA_FROM_DEVICE to mean
 220 * that data is coming from the target (eg handling a READ).  However,
 221 * this is just the opposite of what we have to tell the DMA mapping
 222 * layer -- eg when handling a READ, the HBA will have to DMA the data
 223 * out of memory so it can send it to the initiator, which means we
 224 * need to use DMA_TO_DEVICE when we map the data.
 225 */
 226static inline enum dma_data_direction
 227target_reverse_dma_direction(struct se_cmd *se_cmd)
 228{
 229        if (se_cmd->se_cmd_flags & SCF_BIDI)
 230                return DMA_BIDIRECTIONAL;
 231
 232        switch (se_cmd->data_direction) {
 233        case DMA_TO_DEVICE:
 234                return DMA_FROM_DEVICE;
 235        case DMA_FROM_DEVICE:
 236                return DMA_TO_DEVICE;
 237        case DMA_NONE:
 238        default:
 239                return DMA_NONE;
 240        }
 241}
 242
 243#endif /* TARGET_CORE_FABRICH */
 244